1. Technical Field
The invention relates to a plain bearing composite material and to uses and a method for producing the plain bearing composite material.
2. Related Art
Known from DE 40 04 703 A1 is a layer material for plain bearing elements comprising a metal supporting layer and a an aluminium-based bearing material. The aluminium alloy comprises 1-3 wt. % nickel, 0.5-2.5 wt. % manganese, 0.02-1.5 wt. % copper. 0.5-20 wt. % tin and the remainder being aluminium with the usual impurities. The bearing alloy further contains certain fractions of hard particles substantially in particle sizes ≦5 μm.
In this layer material, an intermediate layer of pure aluminium is provided as an option to improve the bond between the steel back and the bearing material. This plain bearing composite material has good fatigue strength values under a loading up to 80 MPa, good wear resistance and good corrosion safety values.
When this plain bearing composite material with pure aluminium as an intermediate layer is used under fairly high loadings, that is at loadings above 80 MPa, it has been found that the material, in particular that of the intermediate layer, deviates laterally at layer thicknesses >80 μm which, as a result of an enlargement of the bearing width, can lead to a perturbing axial projection in bearing shells or bearing bushings and can thereby even result in failure of the motor.
Known from DE 36 40 328 A1 is a layer material for plain bearing elements comprising an aluminium alloy which differs from the aluminium alloy of DE 40 04 703 A1 by omitting the zinc fraction.
This aluminium bearing alloy is used as a bearing material which allows loading capacities up to 80 MPa before fatigue cracks can be detected in the bearing material layer.
US 2002/0104876 describes a layer composite material comprising a steel back, an aluminium-based intermediate layer with a thickness of 60-120 μm and comprising a bearing metal layer made of an aluminium alloy. The bearing metal layer contains 4-20% lead or tin, up to 26% silicon, up to 2% magnesium, manganese, nickel, tin, copper or chromium. The intermediate layer preferably consists of pure aluminium or an aluminium alloy such as, for example AlMnCu1. The fatigue strength of the layer composite material is a max. 100 MPa. The intermediate layer is joined to the bearing metal layer by means of a hot rolling cladding process.
All layer composite materials have the production-technology disadvantage that the material for the intermediate layer and the material for the bearing layer cannot be produced without considerable expenditure on the same casting system.